How to put gui's on a Part?

i don't know how to put a gui on a part and i want to learn how so i can do more better things with gui's

SurfaceGui

Insert the SurfaceGui into the part or into a Player's PlayerGui. If it's in a Part, all players will see it, otherwise only the player will see it. If it is in a PlayerGui you will need to set the Adornee to the Part you want to put it on.

You'll need to change the side that the SurfaceGui puts its stuff on.

The SurfaceGui acts just like a ScreenGui of a fixed size.